1. Field of Invention
This invention relates to ramps. In particular, this invention relates to wheelchair ramps wherein an adjustable supporting means is attached to the ramps to support them at a variety of heights.
2. Prior Art
Conventional wheelchair ramps are essentially of two types. The first type is a pair of generally "C" shaped ramps, each of which is generally comprised of two or three sections for descending relatively small heights, such as with one or two steps. The second general type of ramp is a one piece ramp designed for use where the drop is also relatively short. These types of ramps are disclosed, for example, in the publication titled "Porta-Ramp" produced by Crump Products, Inc.
Although both of these types of ramps serve important functions, there are many situations where a different, more adaptable ramp should be useful. For example, if the height of drop from the top of the surface to the landing area is too great, relatively short ramps, i.e., about six feet or less, are not practical since a person in a wheelchair using the ramp may travel down the ramp at too great a speed and risk falling.
To overcome this deficiency, ramps of greater length are needed. This lengthening of the ramps, however, creates additional problems. If the same type of material is used for construction of the lengthened ramps as is commonly used in conventional ramps, these lengthened ramps will bend while in use resulting in an increased likelihood of an accident. Further, such stress on the ramps will greatly reduce the useful life of the ramp.
One method of lessening this problem would be to increase the strength and thickness of the ramp material so that it could support the weight of an individual in a wheelchair over a distance of eight feet or more. However, such an increase in thickness creates additional problems, not the least of which are the increase in price of the product and the dramatic increase in the weight of the ramp, thus making the product not practical.
If conventional one piece ramps are increased in length, similar problems will also occur. To allow the individual in the wheelchair to safely negotiate an increased length of drop, the ramp would have to be lengthened which would greatly increase its weight. If, in the alternative, lighter materials are used to reduce the weight of the ramp and make it more practical, the ramp would tend to bend or buckle when in use.
Therefore, it is an object of this invention to provide a wheelchair ramp which will allow for safe passage by an individual in a wheelchair over relatively long distances.
It is another object of this invention to provide a wheelchair ramp which is supported by supporting legs which can be adjusted to various heights depending on the angle of the incline.
It is a still further object of this invention to provide a wheelchair ramp which will allow for a safe ascent or descent by an individual in a wheelchair from a relatively great height.
It is a still further object of this invention to provide a safe, reliable, adjustable height wheelchair ramp which is not heavy and which can be easily stored.
These and other objects and features of the present invention will become apparent to those skilled in the art from a consideration of the following detailed description, drawings and claims. A description along with the accompanying drawings provides a selected example of construction of the device to illustrate the invention.